The investigation of congenital infection by Trypanosoma cruzi in an endemic area of Chile: three protocols explored in a pilot project.

Given the increasing travel of pregnant women from areas were Trypanosoma cruzi is endemic, the congenital transmission of the parasite has become a global public-health problem. In a recent pilot study, which ran in Chile from 2006 to 2010, three strategies for exploring and managing T. cruzi-infected mothers and their infected or uninfected neonates were investigated. Any protocols applied to the investigation of such mother-and-child pairs need to include the detection of infection in pregnant women, the detection of infection, if any, in the children born to the women, the appropriate treatment of the infected neonates, and the serological-parasitological follow-up of all of the neonates until their medical discharge.

Multiple mechanisms confer drug resistance to mitoxantrone in the human 8226 myeloma cell line.

Selection for in vitro drug resistance can result in a complex phenotype with more than one mechanism of resistance emerging concurrently or sequentially. We examined emerging mechanisms of drug resistance during selection with mitoxantrone in the human myeloma cell line 8226. A novel transport mechanism appeared early in the selection process that was associated with a 10-fold resistance to mitoxantrone in the 8226/MR4 cell line. The reduction in intracellular drug concentration was ATP-dependent and ouabain-insensitive. The 8226/MR4 cell line was 34-fold cross-resistant to the fluorescent aza-anthrapyrazole BBR 3390. The resistance to BBR 3390 coincided with a 50% reduction in intracellular drug concentration. Confocal microscopy using BBR 3390 revealed a 64% decrease in the nuclear:cytoplasmic ratio in the drug-resistant cell line. The reduction in intracellular drug concentration of both mitoxantrone and BBR 3390 was reversed by a novel chemosensitizing agent, fumitremorgin C. In contrast, fumitremorgin C had no effect on resistance to mitoxantrone or BBR 3390 in the P-glycoprotein-positive 8226/DOX6 cell line. Increasing the degree of resistance to mitoxantrone in the 8226 cell line from 10 to 37 times (8226/MR20) did not further reduce the intracellular drug concentration. However, the 8226/MR20 cell line exhibited 88 and 70% reductions in topoisomerase II beta and alpha expression, respectively, compared with the parental drug sensitive cell line. This decrease in topoisomerase expression and activity was not observed in the low-level drug-resistant, 8226/MR4 cell line. These data demonstrate that low-level mitoxantrone resistance is due to the presence of a novel, energy-dependent drug efflux pump similar to P-glycoprotein and multidrug resistance-associated protein. Reversal of resistance by blocking drug efflux with fumitremorgin C should allow for functional analysis of this novel transporter in cancer cell lines or clinical tumor samples. Increased resistance to mitoxantrone may result from reduced intracellular drug accumulation, altered nuclear/cytoplasmic drug distribution, and alterations in topoisomerase II activity.

Predictive factors for successful early prosthetic ambulation among lower-limb amputees.

OBJECTIVE: To predict successful prosthetic ambulation for patients immediately transferred to an inpatient rehabilitation facility after amputation surgery. METHODS: Seventy-five individuals with lower-limb amputation were studied at a tertiary acute care and rehabilitation facility. Successful prosthetic ambulation, defined as the ability to ambulate with a prosthesis at least 45 m, was measured in addition to other key demographic and medical factors. RESULTS: Sixty-eight percent were successful prosthetic ambulators at rehabilitation discharge. The absence of residual-limb contracture and a longer length of stay during rehabilitation showed a significant relationship to successful prosthetic ambulation with regression analysis. Younger age was modestly correlated to outcome. There were no significant differences when comparing success of the early rehabilitation program with surgical level or etiology of amputation. For successful prosthetic users, mean wear time at rehabilitation discharge was 5.7 hours with a mean distance walked of 67 m. Of those who failed this approach, 70% were related to a failure of wound healing. CONCLUSIONS: In this cohort, 68% of patients who were selected for a trial of early prosthetic rehabilitation ambulated using a prosthesis at rehabilitation discharge. This approach appears to be more effective for younger patients without contractures who are medically stable to participate in the rehabilitation process.

Ketorolac, a new non-opioid analgesic: a double-blind trial versus pentazocine in cancer pain.

A randomized double-blind trial was performed to evaluate the efficacy of a new non-steroidal anti-inflammatory analgesic drug, ketorolac, in the treatment of cancer pain compared with the opioid pentazocine. A total of 40 patients with moderate to severe cancer pain were studied, 20 patients being treated with 10 mg ketorolac given orally every 6 h and 20 receiving 50 mg pentazocine given orally every 6 h for up to 7 days. A reduction in the severity of the pain was recorded in both treatment groups with no significant difference in efficacy being found between the two therapies, although withdrawals due to adverse reactions were significantly less in the ketorolac-treated group (p less than 0.005). It is concluded that ketorolac may be a useful and more acceptable alternative to opioids in the treatment of cancer pain.

[Bronchiolitis obliterans with idiopathic organized pneumonia. Apropos of 4 cases]. / Bronquiolitis obliterante con neumonía organizada idiopática. A propósito de cuatro casos.

We report 4 cases of idiopathic bronchiolitis obliterans with organizing pneumonia. With this motive, we asses the clinical and radiologic features, lung function tests and response to treatment of our cases. Our findings, in general, are coincident with other authors. It's an entity with nonspecific respiratory symptoms that one must suspect in presence of alveolar patchy opacities on chest roentgenogram that do not respond to antibiotics. The diagnosis is based on histopathologic findings with lung biopsy and the treatment on corticosteroids, with favorable evolution in the majority of the cases.

[Role of bronchoalveolar lavage and transbronchial biopsy in the diagnosis of pneumonia in patients with organ transplantation]. / Papel del lavado broncoalveolar y la biopsia transbronquial en el diagnóstico de neumonías en pacientes portadores de trasplante de órganos.

Pneumonia in patients with organ transplantation constitutes a very frequent cause of mortality, as a result precocious aetiologic diagnosis is indispensable. The bronchoscopic techniques, bronchoalveolar lavage (BAL) and transbronchial biopsy (TBB), constitute fundamental procedures for these diagnoses. We begin this study with the aim of evaluating the profitability obtained with these procedures. 36 bronchoscopies were performed on 29 patients with organ transplantation, in all of them we realized BAL and in 20 TBB. We confirm the presence of pneumonia in 30 (in 15 of them we had performed TBB), the BAL was diagnostic in 20 cases (66.6%) and the TBB in 7 (46.6%). With both, BAL and TBB, we obtained a sensitivity of 80% and a specificity of 75%. We isolated 10 bacteria, 8 Citomegalovirus (CMV), 6 Pneumocystis carinii and 2 Aspergillus fumigatus. The BAL and the TBB contributed significantly in the aetiologic diagnosis of pneumonia in patients with organ transplantation, consequently we consider them basic tools in the management of these infections.

Evaluación de la fatiga en pacientes con artritis psoriásica y su asociación con otras variables de la enfermedad / Evaluation of fatigue in patients with psoriatic arthritis and association with other variables of the disease

Objetivo: Evaluar la frecuencia de fatiga en pacientes con APs y su asociación con otras variables de la enfermedad. Métodos: Pacientes ≥18 años con diagnóstico de APs según criterios CASPAR. Se evaluó fatiga, rigidez matinal, dolor, actividad de la enfermedad por el paciente y el médico por escala visual graduada (EVG). Se completaron los autocuestionarios ASQoL, PsAQoL, HAQ-A, BASFI y BASDAI. Se calcularon los índices compuestos DAS28, DAPSA y CPDAI. Resultados: Se incluyeron 112 pacientes. La mediana de fatiga fue de 3 cm (RIC 0-6). Fatiga tuvo aceptable correlación con BASDAI (r:0,63), pregunta Nº1 del BASDAI (r:0,48), DAS28 (r:0,45), DAPSA (r:0,5), HAQ-A (r:0,42), PsAQoL (r:0,49), ASQoL (r:0,48), BASFI (r:0,47), EVG de dolor (r:0,48) y de rigidez matinal (r:0,55). El 30% de nuestra cohorte presentó fatiga definida como EVG ≥6 cm. En el análisis de regresión lineal múltiple, la actividad de la enfermedad articular periférica (DAPSA coef β: 0,36, p=0,0001) y la calidad de vida (PsAQoL coef β: 0,27, p=0,009) se asociaron significativamente a fatiga. Conclusión: El 30% de nuestra cohorte de pacientes presentó EVG de fatiga ≥6 cm. La fatiga se asoció independientemente con la actividad de la enfermedad articular periférica y la calidad de vida.

Objective: To evaluate the frequency of fatigue in patients with PsA and its association with other disease variables. Methods: We included patients ≥18 years of age with PsA according to CASPAR criteria. Fatigue, morning stiffness, pain and global activity by both patients and physicians were assessed using visual analogue scales (VAS). ASQoL, PsAQoL, HAQ-A, BASFI and BASDAI were completed. DAS28, DAPSA and CPDAI were calculated. Results: We included 112 patients. Median fatigue VAS was 3 cm (IQR 0-6). Fatigue had an acceptable correlation with BASDAI (r:0.63), BASDAI question Nº1 (r:0.48), DAS28 (r:0.45), DAPSA (Rho:0.5), HAQ-A (Rho:0.42), PsAQoL (Rho:0.49), ASQoL (Rho:0.48), BASFI (Rho:0.47), pain (Rho:0.48) and morning stiffness (Rho:0.55) and a regular correlation with CPDAI (Rho:034). 30% of our cohort had fatigue, as defined by a VAS equal or greater than 6 cm. In multiple linear regression analysis, adjusting for sex, age and disease duration, peripheral disease activity (DAPSA βcoeff: 0.36, p=0.0001) and quality of life (PsAQoL βcoeff: 0.27, p=0.009) were associated with fatigue. Conclusion: Prevalence of fatigue in this cohort was 30% and it was associated with greater peripheral disease activity and worse quality of life.

Organophosphate pesticides increase the expression of alpha glutathione S-transferase in HepG2 cells.

Chlorpyrifos and methyl parathion are among the most widely used insecticides in the world. Human populations are constantly exposed to low doses of both due to their extensive use and presence in food and drinking water. Glutathione S-transferase (GST) catalyzes the conjugation of glutathione on electrophilic substrates and is an important line of defense in the protection of cellular components from reactive species. GST alpha1 (GSTA1) is the predominant isoform of GST expressed in the human liver; thus, determining the effect of insecticides on GSTA1 transcription is very important. In the present study, we analyzed the effects of methyl parathion and chlorpyrifos on GSTA1 gene expression in HepG2 cells using real time PCR, and activity and immunoreactive protein assays. The results demonstrated that exposure to methyl parathion and chlorpyrifos increased the level of GSTA1 mRNA, GSTA1 immunoreactive protein and GST activity relative to a control. These results demonstrated that these insecticides can increase the expression of GSTA1. In conclusion, HepG2 cell cultures treated with methyl parathion and chlorpyrifos could be a useful model for studying the function of GSTA1 and its role in the metabolism of xenobiotics in the liver.

[Effect of miocamycin and erythromycin on the activity of human neutrophils against Staphylococcus aureus]. / Efecto de miocamicina y eritromicina en la actividad de los neutrófilos humanos sobre Staphylococcus aureus.

We evaluate the effect of two macrolide drugs (miocamycin and erythromycin) on human neutrophil cells (PMNs) against S. aureus strains. We studied: a) S. aureus pre-treatment effect, using subinhibitory concentrations of the two drugs, on its phagocytosis by human PMN's; b) effect of the drugs on superoxide production by PMN's; c) intracellular activity of the two drugs against S. aureus. Prior treatment of S. aureus with subinhibitory concentrations (25% of the MIC) increases significantly the phagocytosis of opsonized bacteria by human PMN's. Using non-opsonized bacteria, the registered effect was only statistically significant for miocamycin. Pre-incubation of human PMN's with 1, 10 and 25 mg/L concentrations of each drug did not influence superoxide production of the cells. Both drugs showed slight intracellular activity against S. aureus inside human PMN's, although this only achieves statistically significant difference with higher concentrations (25 mg/L) of miocamycin. In summary, both drugs influence directly human PMN's phagocytosis of S. aureus, changing the opsonic requirements of the microorganism. At therapeutic levels, neither erythromycin nor miocamycin hampered phagocytic and bactericidal mechanisms of human PMN's. At higher concentration, miocamycin showed good intracellular activity against S. aureus.

Uptake and intracellular activity of sparfloxacin in human polymorphonuclear leukocytes and tissue culture cells.

The penetration of sparfloxacin into human neutrophils (PMN) and different tissue culture cells (HEp-2 and McCoy) was evaluated. The cellular to extracellular concentration ratios (C/E) of sparfloxacin were always higher than 4 at extracellular concentrations ranging from 0.5 to 25 mg/liter. The uptake of sparfloxacin by PMN was rapid, nonsaturable, reversible, not energy dependent, and significantly reduced at pH 8. The penetration of this agent into PMN was similar when viable and Formalin-killed cells were used and was not affected by environmental temperature. Ingestion of opsonized zymosan significantly increased the amount of PMN-associated sparfloxacin. Sparfloxacin at a concentration of 0.5 mg induced a significant reduction in the survival of intracellular Staphylococcus aureus. It is concluded that sparfloxacin reaches intracellular concentrations within leukocytic cells much higher than extracellular concentrations, while remaining active intracellularly.

A randomized trial comparing chlorambucil plus prednisone vs cyclophosphamide, melphalan, and prednisone in the treatment of chronic lymphocytic leukemia stages B and C.

Ninety-six previously untreated patients (67 males/29 females; mean age: 63 years; range: 46-84) with CLL in stage B (62 cases) or C (34 cases) were randomized to be treated with either chlorambucil (0.4 mg/kg orally days 5 and 6) plus prednisone (60 mg/m2 orally days 1 to 4) (CL + PDN) every 2 weeks or cyclophosphamide (160 mg/m2 orally days 1 to 4), melphalan (6 mg/m2 orally days 1 to 4), and prednisone (60 mg/m2 orally days 1 to 4) (CMP) every 3 weeks for 10 months. Forty-eight patients were treated with CLR + PDN, and the remaining 48 with CMP. The following types of response were considered: complete response (CR): total disappearance of symptoms and signs related to the disease. Partial response (PR): shift of the disease to a less advanced stage. Stable disease (SD) no change in the stage after treatment. Progressive disease (PD): progression of the disease to a more advanced stage. Thirty-six (75%) responses (27% CR) with CLR + PDN and 26 (54.5%, 12.5% CR) with CMP were observed (p = 0.054). Although more responses were achieved in stage B (69%, 24% CR) than in stage C (54%, 12% CR) this difference did not achieve statistical significance. Survival was statistically not different for those patients treated with LCR + PDN as compared to those receiving CMP.(ABSTRACT TRUNCATED AT 250 WORDS)

Molecular modeling, synthesis, and structures of N-methylated 3,5-linked pyrrolin-4-ones toward the creation of a privileged nonpeptide scaffold.

The molecular modeling, synthesis, and elucidations of the solid state and solution structures of N-methylated 3,5-linked bispyrrolin-4-ones are described. Prior investigations established that the 3,5-linked pyrrolin-4-one based scaffold can be incorporated into mimics of beta-sheet/beta-strands and into potent, orally bioavailable inhibitors of the HIV-1 protease. To extend the utility of this scaffold beyond that of the initially designed mimics of beta-sheet/beta-strands, we have now explored the structure of N-methylated pyrrolinones. Molecular modeling indicated that N-methylated bispyrrolinones could adopt three low-energy backbone conformations (ca. 165 degrees, 289 degrees, and 320 degrees). Upon their successful synthesis, structural elucidation both in the solid state and in solution revealed the existence of two of the three predicted backbone conformers (ca. 165 degrees and 289 degrees). Two structures were particularly noteworthy and completely unexpected. Mono-N-methyl bispyrrolinone (+)-1 self assembled in the solid state to form a novel helix, while the acetylene-linked dimer of (+)-1, designed to potentiate the observed helical array, instead associated via an intermolecular hydrogen bond in parallel columns. These serendipitous observations led us to speculate that the pyrrolinone moiety may in fact represent a privileged nonpeptide scaffold, able to mimic not only the extended beta-sheet/beta-strand conformation as initially targeted, but also diverse conformations including those analogous to beta-turns and helices. These seemingly unlimited conformations greatly expand the scope of this scaffold for the development of low-molecular weight ligands for biologically important macromolecules.

Selection for drug resistance results in resistance to Fas-mediated apoptosis.

Recent evidence has supported the hypothesis that chemotherapeutic drugs and radiation induce an apoptotic pathway that requires the active participation of the cell. One pathway of apoptosis in malignant lymphoid cells is mediated by the Fas antigen. We studied the human myeloma (8226) and T-cell leukemia (CEM) cell lines selected for resistance to the anthracenes, doxorubicin or mitoxantrone, by continuous culture in the presence of either agent. We found that these drug-resistant cell lines were also resistant to Fas-mediated apoptosis in a dose-dependent manner. The degree of resistance to Fas-mediated apoptosis correlated directly with the level of resistance to chemotherapeutic drugs. These observations indicate that, as cancer cell lines develop mechanisms of drug resistance, they may also develop mechanisms of resistance to physiologic signals of apoptosis. Two mechanisms of resistance to Fas-mediated apoptosis were observed in these cell lines. One mechanism was associated with a dose-dependent reduction in the surface expression of Fas antigen. Analysis of RNA by reverse transcriptase-polymerase chain reaction assays showed that the reduction of Fas antigen expression occurred at the level of transcription. A second mechanism of drug resistance showed no decrease of Fas antigen expression; however, the apoptotic response was diminished. In this situation, removal of the chemotherapeutic agent resulted in a partial reversion to chemosensitivity and re-expression of the Fas antigen, but these cell lines did not regain the ability to undergo apoptosis in response to cross-linking by anti-Fas antibody. These findings support the hypothesis that apoptosis mediated by both chemotherapeutic agents and physiologic stimuli may share a common downstream effector. The demonstration that selection for drug resistance in hematopoietic cell lines results in a simultaneous resistance to Fas-mediated apoptosis may have clinical implications in the development of strategies for the treatment of resistant disease. Further analysis of the molecular mechanisms of Fas expression and function will facilitate the design of biological response modifying agents for the treatment of malignancy.

Resistance to the chemosensitizer verapamil in a multi-drug-resistant (MDR) human multiple myeloma cell line.

Inhibitors of P-glycoprotein (P-gp) or chemosensitizers, such as verapamil, are used to reverse multi-drug resistance (MDR) in cancer patients. Clinical studies in patients with myeloma have shown that some patients with P-gp-positive cancer cells respond to the chemosensitizing effect of verapamil. However, this response is short-lived and tumor cells ultimately become resistant to chemosensitizers. To study mechanisms of resistance to chemosensitizers, a human myeloma cell line, 8226/MDR10V, was selected from a P-gp-positive cell line, 8226/Dox40, in the continuous presence of doxorubicin and verapamil. MDR10V cells are consistently more resistant to MDR drugs than parent cells, Dox40. Chemosensitizers, including verapamil and cyclosporin A, were less effective in reversing resistance in MDR10V compared with Dox40 cells. Verapamil and cyclosporin A were only partially effective in blocking P-gp drug efflux in MDR10V compared to Dox40 cells. Despite higher resistance to cytotoxic agents, MDR10V cells express less P-gp in the plasma membrane than do its parent cells, Dox40. [3H]Azidopine photoaffinity labeling of P-gp and its binding competition with unlabeled verapamil showed similar affinity for P-gp between Dox40 and MDR10V cell lines. Non-P-gp-mediated mechanisms of drug resistance, including over-expression of MRP and alterations in topoisomerase II, were not different for MDR10V cells compared with Dox40 cells.

Design and synthesis of nonpeptide peptidomimetic inhibitors of renin.

The desire to replace the amide backbone of renin inhibitors with a new scaffold led us to explore vinylogous amides (enaminones). An initial attempt proved unsuccessful, a result explained after the fact via docking experiments. Based on this lesson, we designed a different vinylogous amide scaffold which incorporated one or more pyrrolinone rings into the backbone. Three of the four compounds gave IC50S in the 0.6 to 18 microM range. These compounds did not inhibit HIV-1 protease. Taken together, the results reported herein provide insights into the role of hydrogen bonding and steric interactions for binding to renin.

Verapamil suppresses the emergence of P-glycoprotein-mediated multi-drug resistance.

Selection protocols were designed to determine whether non-cytotoxic chemomodifiers can influence the evolution of the drug-resistant phenotype. To this end, the human multiple myeloma cell line RPMI 8226 (8226/S) was selected with either doxorubicin, verapamil or doxorubicin plus verapamil. Using this approach low-level multi-drug-resistant (MDR) cell lines were obtained when 8226/S was selected with doxorubicin only or doxorubicin plus verapamil but not with verapamil only. The MDR phenotypes obtained were mechanistically distinct. In doxorubicin only-selected cells (8226/dox4), drug resistance was mediated by over-expression of the MDR1 gene and its cognate protein P-glycoprotein. In contrast, the drug resistance seen in the doxorubicin plus verapamil-selected cells was mediated through decreases in topoisomerase II protein levels and catalytic activity and not by P-glycoprotein over-expression. Cells selected with verapamil alone did not become resistant to any of the drugs tested. None of the 3 selected cell lines showed any changes in MRP gene expression when compared with 8226/S. Our results indicate that the inclusion of verapamil during drug selection with doxorubicin influences the drug-resistant phenotype by preventing the selection of MDR1/P-glycoprotein-positive cells.